linux/drivers/pci/hotplug/cpcihp_generic.c
Akinobu Mita 49c61cca2b cpcihp_generic: prevent loading without "bridge" parameter
cpcihp_generic module requires configured "bridge" module parameter.
But it can be loaded successfully without that parameter.
Because module init call ends up returning positive value.

This patch prevents from loading without setting "bridge" module parameter.

Signed-off-by: Akinbou Mita <akinobu.mita@gmail.com>
Signed-off-by: Scott Murray <scottm@somanetworks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-10-18 11:36:12 -07:00

224 lines
6.2 KiB
C

/*
* cpcihp_generic.c
*
* Generic port I/O CompactPCI driver
*
* Copyright 2002 SOMA Networks, Inc.
* Copyright 2001 Intel San Luis Obispo
* Copyright 2000,2001 MontaVista Software Inc.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*
* This generic CompactPCI hotplug driver should allow using the PCI hotplug
* mechanism on any CompactPCI board that exposes the #ENUM signal as a bit
* in a system register that can be read through standard port I/O.
*
* Send feedback to <scottm@somanetworks.com>
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/pci.h>
#include <linux/string.h>
#include "cpci_hotplug.h"
#define DRIVER_VERSION "0.1"
#define DRIVER_AUTHOR "Scott Murray <scottm@somanetworks.com>"
#define DRIVER_DESC "Generic port I/O CompactPCI Hot Plug Driver"
#if !defined(MODULE)
#define MY_NAME "cpcihp_generic"
#else
#define MY_NAME THIS_MODULE->name
#endif
#define dbg(format, arg...) \
do { \
if(debug) \
printk (KERN_DEBUG "%s: " format "\n", \
MY_NAME , ## arg); \
} while(0)
#define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME , ## arg)
#define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME , ## arg)
#define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME , ## arg)
/* local variables */
static int debug;
static char *bridge;
static u8 bridge_busnr;
static u8 bridge_slot;
static struct pci_bus *bus;
static u8 first_slot;
static u8 last_slot;
static u16 port;
static unsigned int enum_bit;
static u8 enum_mask;
static struct cpci_hp_controller_ops generic_hpc_ops;
static struct cpci_hp_controller generic_hpc;
static int __init validate_parameters(void)
{
char* str;
char* p;
unsigned long tmp;
if(!bridge) {
info("not configured, disabling.");
return -EINVAL;
}
str = bridge;
if(!*str)
return -EINVAL;
tmp = simple_strtoul(str, &p, 16);
if(p == str || tmp > 0xff) {
err("Invalid hotplug bus bridge device bus number");
return -EINVAL;
}
bridge_busnr = (u8) tmp;
dbg("bridge_busnr = 0x%02x", bridge_busnr);
if(*p != ':') {
err("Invalid hotplug bus bridge device");
return -EINVAL;
}
str = p + 1;
tmp = simple_strtoul(str, &p, 16);
if(p == str || tmp > 0x1f) {
err("Invalid hotplug bus bridge device slot number");
return -EINVAL;
}
bridge_slot = (u8) tmp;
dbg("bridge_slot = 0x%02x", bridge_slot);
dbg("first_slot = 0x%02x", first_slot);
dbg("last_slot = 0x%02x", last_slot);
if(!(first_slot && last_slot)) {
err("Need to specify first_slot and last_slot");
return -EINVAL;
}
if(last_slot < first_slot) {
err("first_slot must be less than last_slot");
return -EINVAL;
}
dbg("port = 0x%04x", port);
dbg("enum_bit = 0x%02x", enum_bit);
if(enum_bit > 7) {
err("Invalid #ENUM bit");
return -EINVAL;
}
enum_mask = 1 << enum_bit;
return 0;
}
static int query_enum(void)
{
u8 value;
value = inb_p(port);
return ((value & enum_mask) == enum_mask);
}
static int __init cpcihp_generic_init(void)
{
int status;
struct resource* r;
struct pci_dev* dev;
info(DRIVER_DESC " version: " DRIVER_VERSION);
status = validate_parameters();
if (status)
return status;
r = request_region(port, 1, "#ENUM hotswap signal register");
if(!r)
return -EBUSY;
dev = pci_find_slot(bridge_busnr, PCI_DEVFN(bridge_slot, 0));
if(!dev || dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
err("Invalid bridge device %s", bridge);
return -EINVAL;
}
bus = dev->subordinate;
memset(&generic_hpc, 0, sizeof (struct cpci_hp_controller));
generic_hpc_ops.query_enum = query_enum;
generic_hpc.ops = &generic_hpc_ops;
status = cpci_hp_register_controller(&generic_hpc);
if(status != 0) {
err("Could not register cPCI hotplug controller");
return -ENODEV;
}
dbg("registered controller");
status = cpci_hp_register_bus(bus, first_slot, last_slot);
if(status != 0) {
err("Could not register cPCI hotplug bus");
goto init_bus_register_error;
}
dbg("registered bus");
status = cpci_hp_start();
if(status != 0) {
err("Could not started cPCI hotplug system");
goto init_start_error;
}
dbg("started cpci hp system");
return 0;
init_start_error:
cpci_hp_unregister_bus(bus);
init_bus_register_error:
cpci_hp_unregister_controller(&generic_hpc);
err("status = %d", status);
return status;
}
static void __exit cpcihp_generic_exit(void)
{
cpci_hp_stop();
cpci_hp_unregister_bus(bus);
cpci_hp_unregister_controller(&generic_hpc);
release_region(port, 1);
}
module_init(cpcihp_generic_init);
module_exit(cpcihp_generic_exit);
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
module_param(bridge, charp, 0);
MODULE_PARM_DESC(bridge, "Hotswap bus bridge device, <bus>:<slot> (bus and slot are in hexadecimal)");
module_param(first_slot, byte, 0);
MODULE_PARM_DESC(first_slot, "Hotswap bus first slot number");
module_param(last_slot, byte, 0);
MODULE_PARM_DESC(last_slot, "Hotswap bus last slot number");
module_param(port, ushort, 0);
MODULE_PARM_DESC(port, "#ENUM signal I/O port");
module_param(enum_bit, uint, 0);
MODULE_PARM_DESC(enum_bit, "#ENUM signal bit (0-7)");